/Engine/Source/Runtime/GeometryFramework/Public/UDynamicMesh.h
Take ownership of the internal Mesh, and have it replaced with a new mesh
[TUniquePtr](API\Runtime\Core\Templates\TUniquePtr)< [UE::Geometry::FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) > ExtractMesh()